Menu

Herbicide May Harm Microbiome of Bees

Glyphosate perturbs the balance of gut bacteria in honey bees and increases the insects’ susceptibility to lethal infection.

Sep 26, 2018

Iris Kulbatski

ABOVE: Studying the gut microbiome of bees provides insight into the insects' overall health and resistance to infection.PIXABAY, POLLYDOT

Consuming a mixture of sugar syrup and glyphosate, the active ingredient in Monsanto’s Roundup herbicide, alters honey bees’ microbiomes, and these changes increased mortality among insects exposed to pathogenic bacteria, according to a study published yesterday (September 24) in PNAS.

Glyphosate is the most commonly used herbicide worldwide. It acts by blocking a key plant enzyme used in the production of amino acids. Researchers are divided on whether the chemical is safe to animals at the levels it is usually used as a herbicide. However, some bacteria are known to produce this enzyme, and the new study demonstrates what some researchers have suspected: glyphosate may harm animals indirectly by killing their resident microbes.

Nancy Moran of the University of Texas at Austin and colleagues found that glyphosate consumption can lower the levels of the common bee symbiont Snodgrassella alvi by up to five times in the guts of honey bees, and high levels of the herbicide thwarted growth of S. alvi in vitro. Moreover, bees were more susceptible to infection by Serratia marcescens, a bacterium commonly present at low levels in beehives, after drinking the glyphosate–sugar water cocktail: only 12 percent of the insects survived, compared with 47 percent of infected bees that had not been fed glyphosate.

Given these findings, more research is warranted to determine whether the proposed mechanism of honey bee morbidity contributes significantly to issues of colony collapse and overall rates of honey bee decline worldwide, University of Illinois bee geneticist Gene Robinson tells Science.

Moreover, the current study raises the possibility that glyphosate may alter the gut microbiome of other animals, including humans, Moran tells Science.

In vitro work has been generally unable to capture the intricate interplay so vital to regulating function and homeostasis. In vivo imaging represents a solution to that uncertainty. Download this eBook from AnalytikJena to find out how in vivo imaging gives scientists the ability to bridge the gap between the petri dish and the animal model!

Lentiviruses are powerful tools in molecular biology. Download this eBook to learn about the basics of lentivirus preparation and production, working with lentiviruses, and counting and storing lentiviruses.

Researchers at the University of Zurich in Switzerland are using INTEGRA’s VIAFLO 96/384 multichannel electronic pipette to streamline the experimental workflow of studies on Pseudomonas aeruginosa – a bacterium that commonly infects individuals with lung conditions, such as cystic fibrosis.